Removing catalytic converter

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PoloB
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Removing catalytic converter

Post by PoloB »

Hi,

Has anyone removed the cat on their vehicles any advice if I want to remove mine what needs to stay and what can go?

What is the implication of removing the cat, any warning lights etc. that would need to be cancelled?

Reason for asking is my exhaust silencer box first one after engine has cracked open at the seam (apparently a common polo problem) vehicle just done 36756km still under warranty but don't really care as I would rather want to go with performance setup as the OEM sounds terribly kak!!!(Only 2 months left of warranty anyway)

So I was thinking of removing the whole OEM system and doing a 4-1 Branch setup from Autowerkz in Durban and going with a stainless freeflow.

Any advice will be greatly appreciated.
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ICE King
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Re: Removing catalytic converter

Post by ICE King »

Your options are as follows:

1. Remove Cat and re weld on flange onto new exhaust for Cat Sensor- Probably the easiest
2. Remove Cat and sensor, install resistor for sensor circuit to close
3. Remove Cat and delete Cat sensor from ECU map - Needs Mapping

In short you cannot just remove the sensor without closing the circuit - then you'll have a dash light on.
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PoloB
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Re: Removing catalytic converter

Post by PoloB »

ICE King wrote: Tue Sep 18, 2018 1:30 pm Your options are as follows:

1. Remove Cat and re weld on flange onto new exhaust for Cat Sensor- Probably the easiest
2. Remove Cat and sensor, install resistor for sensor circuit to close
3. Remove Cat and delete Cat sensor from ECU map - Needs Mapping

In short you cannot just remove the sensor without closing the circuit - then you'll have a dash light on.
Can a tech at VW do option 3 on their clever pc's or it this something they won't do?
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Re: Removing catalytic converter

Post by ICE King »

VW wouldn't dare despite having the tools to do so , Will need to locate a " aftermarket" tuner - best closet to your area.

I see your car has software already?
also since you mentioning branch and not down pipe, do you have a non-turbo polo 6?
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PoloB
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Re: Removing catalytic converter

Post by PoloB »

Yes already did software a month ago.

Yes non turbo 1.6 polo
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Re: Removing catalytic converter

Post by PoloB »

ICE King wrote: Tue Sep 18, 2018 1:44 pm VW wouldn't dare despite having the tools to do so , Will need to locate a " aftermarket" tuner - best closet to your area.

I see your car has software already?
also since you mentioning branch and not down pipe, do you have a non-turbo polo 6?
Cant remember if the guy said the Cat delete was included in the software tune or not. Will have to make sure
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Re: Removing catalytic converter

Post by ICE King »

PoloB wrote: Tue Sep 18, 2018 1:56 pm
ICE King wrote: Tue Sep 18, 2018 1:44 pm VW wouldn't dare despite having the tools to do so , Will need to locate a " aftermarket" tuner - best closet to your area.

I see your car has software already?
also since you mentioning branch and not down pipe, do you have a non-turbo polo 6?
Cant remember if the guy said the Cat delete was included in the software tune or not. Will have to make sure
Usually is but will have to make sure, If it is then you good to go for a exhaust system :thumbup:
Will wake the car up nicely at the top of the rev range :evil:
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Re: Removing catalytic converter

Post by PoloB »

ICE King wrote: Tue Sep 18, 2018 3:05 pm
PoloB wrote: Tue Sep 18, 2018 1:56 pm
ICE King wrote: Tue Sep 18, 2018 1:44 pm VW wouldn't dare despite having the tools to do so , Will need to locate a " aftermarket" tuner - best closet to your area.

I see your car has software already?
also since you mentioning branch and not down pipe, do you have a non-turbo polo 6?
Cant remember if the guy said the Cat delete was included in the software tune or not. Will have to make sure
Usually is but will have to make sure, If it is then you good to go for a exhaust system :thumbup:
Will wake the car up nicely at the top of the rev range :evil:

Any suggestions on what size free flow would work best? Don't want a loud blaring sound either just a nice deep growl
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Re: Removing catalytic converter

Post by Gummi »

This is exactly what i wanted to know. Thanx for posting and the replies.
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Re: Removing catalytic converter

Post by ICE King »

PoloB wrote: Wed Sep 19, 2018 7:20 am
ICE King wrote: Tue Sep 18, 2018 3:05 pm
PoloB wrote: Tue Sep 18, 2018 1:56 pm
ICE King wrote: Tue Sep 18, 2018 1:44 pm VW wouldn't dare despite having the tools to do so , Will need to locate a " aftermarket" tuner - best closet to your area.

I see your car has software already?
also since you mentioning branch and not down pipe, do you have a non-turbo polo 6?
Cant remember if the guy said the Cat delete was included in the software tune or not. Will have to make sure
Usually is but will have to make sure, If it is then you good to go for a exhaust system :thumbup:
Will wake the car up nicely at the top of the rev range :evil:

Any suggestions on what size free flow would work best? Don't want a loud blaring sound either just a nice deep growl
50mm mild steel piping , a free flow resonator up front and free flow silencer box at the back ,Gives a nice clean sound , Quiet when idling and loud enough on top , also no drone when cruising high speeds.

Note: Peoples opinions differ , I've always prefer mild steel over stainless - It has a deeper complete tone and absorbs the resonating sound.
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Re: Removing catalytic converter

Post by PoloB »

Thanx for the info,

I would prefer stainless due to the lasting quality as mild steel tends to rust to soon. But yes I also like the deeper exhaust note and not that Mazda Rx7 sound you hear for 1km away.

Might also go with mild steel then and I don't want my car sounding to loud as it a daily drive and use it for long holiday trips, will go mad with a blaring exhaust for 700km
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Dub rox
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Re: Removing catalytic converter

Post by Dub rox »

You could also keep your standard zorst as they are normally stainless. Just do a decat and your ears won't bleed on long trips. Your power and fuel consumption should better provided your not to trigger happy with the results. Just my two cents
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Re: Removing catalytic converter

Post by Gummi »

"Remove Cat and sensor, install resistor for sensor circuit to close"

Would the resistor value be the same for all cars? I have a 2000 model v5 agz engine
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Re: Removing catalytic converter

Post by Dub rox »

Gummi wrote:"Remove Cat and sensor, install resistor for sensor circuit to close"

Would the resistor value be the same for all cars? I have a 2000 model v5 agz engine
Or you could fit a mini cat. They are about R600. I speak under correction but if your sensor is before the cat not neccesary but if it is positioned behind the cat it is. Any one have an opinion on this?

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Re: Removing catalytic converter

Post by Ashveer03 »

If the car has an upstream sensor only (only 1 sensor) it doesnt need a minicat.

If has 2 sensors, upstream and downstream then u will need a minicat as the downstream o2 is a cat efficiency sensor..

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Re: Removing catalytic converter

Post by Gummi »

Well im popping around by Powerflow in next week. Will check then how many sensors and also what they say. As far as i know, 2 sensors take into account what the difference between them are. Not sure what it does with that info though. Will keep you guys posted.
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Re: Removing catalytic converter

Post by PoloB »

Ashveer03 wrote: Sat Sep 22, 2018 7:54 pm If the car has an upstream sensor only (only 1 sensor) it doesnt need a minicat.

If has 2 sensors, upstream and downstream then u will need a minicat as the downstream o2 is a cat efficiency sensor..

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Unfortunately mine has 2 sensors one before and one after :bang: :bang: :bang: :bang:
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Re: Removing catalytic converter

Post by Dub rox »

PoloB wrote:
Ashveer03 wrote: Sat Sep 22, 2018 7:54 pm If the car has an upstream sensor only (only 1 sensor) it doesnt need a minicat.

If has 2 sensors, upstream and downstream then u will need a minicat as the downstream o2 is a cat efficiency sensor..

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Unfortunately mine has 2 sensors one before and one after :bang: :bang: :bang: :bang:
The sensor "down stream" lets you know when the cat is fubar and need replacing. The other measures your co for correct fueling.

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